Sulfur(VI) Fluoride Exchange (SuFEx) chemistry has emerged as a next-generation click reaction, designed to assemble functional molecules quickly and modularly. Here, we report the ex situ generation of trifluoromethanesulfonyl fluoride...

A squaramide‐catalyzed asymmetric Mannich reaction of 3‐fluorooxindoles to isatin‐derived imines for synthesis of fluorinated 3,3′‐bisoxindoles with two contiguous stereocenters under mild conditions was developed. The corresponding 3,3′‐bisoxindoles were obtained in excellent yields with excellent diastereo‐ and enantioselectivities (up to 99% yield, >99:1 dr and >99% ee). What's more, this reaction can be gram‐scaled without compromising yield and stereoselectivity.magnified image

A remote cascade asymmetric inverse-electron-demand oxa-Diels-Alder reaction of allyl ketones with isatin-derived β,γ-unsaturated α-keto esters has been developed in the presence of a chiral bifunctional squaramide catalyst. Taking advantage of the secondary amide activating group, a series of enantioenriched 3,4'-pyranyl spirooxindole derivatives bearing three contiguous chiral centers were attained in high yields (84 to > 99%) with excellent enantioselectivities (96-99% ee). Moreover, the gram-scale synthesis and the construction of 1-benzazepine scaffold by the product were also demonstrated.

In their Review article (DOI: 10.1002/chem.202201491), E. Ismalaj and colleagues summarize synthetic methods to access SF5‐containing compounds and their analogs, which are important building blocks in synthetic chemistry. Applications of these important compounds are also discussed.